Sewing machine



FIG. 1 is a front view of a sewing machine, showing our new design;

FIG. 2 is a rear view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is an underside view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a right side view thereof.

FIG. 7 is a perspective view thereof. 

The ornamental design for a sewing machine, as shown. 